Included in this project are a number of epidemiological studies on diet and cancer. Exposures being assessed in human populations include broad dietary patterns, such as diets high in fat or meat; nutritional status, such as low vitamin A or vitamin C intake; metabolic indices, such as low serum cholestrol; specific food groups, such as the Brassica vegetables, food additives; cooking practices; ethnic foods; etc. Cancers being studied include those of the colon, rectum, breast, esophagus, and lung. Case-control studies have been initiated in areas with usually high rates of presumably diet-related cancers and in communities of immigrants whose cancer rates have been changing concurrently with adoption of new lifestyles. In situations where reliable dietary or biochemical information already exists on a number of individuals, follow-up mechanisms and retrospective cohort studies have been initiated. Interviewing methods and statistical methods that would improve data collection and analysis in nutritional epidemiology are being evaluated. Data from Hanes I and II are being analyzed to provide descriptive baseline information on diet variation and nutrient levels throughout the U.S.